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Origin of “rock cities”, pillars and cleft-conduits in kaolinite-bonded sandstone: New insight from study in sandstone quarry where landforms recently evolve
Bruthans, J. ; Soukup, J. ; Schweigstillová, Jana ; Vaculíková, J. ; Smutek, D. ; Mayo, A. L. ; Falteisek, L.
Based on measurements of relative erodibility, ambient and water-saturated tensile strength at natural and quarry exposures three distinct kinds of surfaces were distinguished (erodible sandstone, sub-vertical fracture surfaces and case hardened surfaces). Erosion proceeded along highly fractured zones.
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Study of Biological Material Attributes by using Image Analysis Methods
Jeřábková, Petra ; Mikula, Milan (referee) ; Zmeškal, Oldřich (advisor)
Within the dissertation thesis “Study of Biological Material Attributes by Using Image Analysis Methods”, attention is focused on monitoring of the application of image analysis methods, mostly a fractal analysis, in studying the properties of various yeast species. The thesis includes determining the number of yeast cells and vegetative propagation of yeast using fractal parameters – fractal measure D and fractal dimension K. Attention is also paid not only to the application of the existing image analysis methods, but also to their renovation. The obtained images were evaluated using the box counting method specified by implementation of wavelet transformation. To monitor yeast cells for a longer time, it was first necessary to prepare a suitable microscopic preparation. To distinguish live and dead cells, the following fluorescent dyes were used: acridine orange, fluorescein diacetate, FUN-1, and Calcofluor White M2R. The images of yeast cells were recorded using a still camera or a CCD camera and microscope. Clips of the same size were obtained from the acquired digital photographs and processed by the HarFA program developed at the Faculty of Chemistry, Brno University of Technology. On the results it is possible to see a change in the fractal dimension depending on time, i.e. on the change of a budding cell structure, or to determine the number and radius of yeast cells upon predefined conditions.
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Biologie rozmnožování u raků
NIKSIRAT HASHJIN, Hamid
The ultrastructure of spermatozoa from six crayfish species were described. The acrosome complex and nucleus are located at the anterior and posterior of the spermatozoon, respectively. The acrosome complex organelle is divided into two main parts: the main body of the acrosome that is a dense inverted cup-shaped structure and organized into three layers of differing electron densities and extended parallel filaments, and the sub-acrosome zone occupying the central part of the acrosome complex, which is divided into two electron dense areas. The spermatozoon of Orconectes limosus is described for the first time. In addition, an acrosome spike in the spermatozoon of Procambarus clarkii is described. Despite a well conserved general structure and similarity of pattern among these spermatozoa, differences in the dimensions of the acrosome within the studied species may be useful to help distinguish the different crayfish. The ultrastructure of the spermatozoon and spermatophore wall of the narrow clawed crayfish Astacus leptodactylus during three stages including freshly ejaculated, post-mating, and after release of the spermatozoon were described and compared. The crayfish spermatophore consists of a sperm mass enveloped by a three layered spermatophore wall. After mating, the thickness of the outer layer of the spermatophore is increased. The matrix in the middle layer of the spermatophore becomes reticulated, and granules inside this layer release their contents. Fibers in the inner layer degrade to small particles. The spermatozoon capsule swells and space between the capsule and the spermatozoon appears. The area of the plasma membrane is increased by wrinkling of the surface and alteration from a single to a multilayered structure at the anterior part of the acrosome. The density of the subacrosome zone increases in the vicinity of the main body of the acrosome. With the onset of fertilization, the layers of the spermatophore are dissolved by female glair glands secretions. The capsule, plasma membrane, and membranous lamellae are eliminated, and bundles of filaments are released. The subacrosome zone loses electron density and retracts. The electron-dense material of the innermost layer of the acrosome is discharged and, together with filaments, forms a filament/droplet structure at the anterior part of the spermatozoon. The most important change is observed in the subacrosome zone, which may play a key role in the fertilization. Also, morphological changes of the spermatozoon after release from the capsule, especially formation of the filament/droplet structure, may contribute to the mechanism of egg-spermatozoon binding in the crayfish.
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Symmetries of the CR sub-Laplacian
Vlasáková, Zuzana ; Souček, Vladimír (advisor) ; Slovák, Jan (referee) ; Šilhan, Josef (referee)
Title: Symmetries of the CR sub-Laplacian Author: Zuzana Vlasáková Department: Charles University Institute of Mathematics Supervisor: Prof. RNDr. Vladimír Souček, DrSc. Author's e-mail address: zuzana.kasarova@email.cz Supervisor's e-mail address: soucek@karlin.mff.cuni.cz Abstract: The aim of this work is to characterize the vector space of symme- try operators of the CR sub-Laplacian. To do this, we define a CR structure on some distinguished submanifold of Cn+1 (it is in fact the big cell in the CR sphere) and write down the CR sub-Laplacian on it. We also define the symmetries of the CR sub-Laplacian in general and using the ambient con- struction, which we introduce in the sequel, we construct all of them. Keywords: CR geometry, CR sub-Laplacian, symmetries of differential op- erator. 1
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Development of HPLC method for assesment of stability of amorphous compounds
Číhalová, Daniela ; Solich, Petr (advisor) ; Sklenářová, Hana (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Daniela Číhalová Supervisor: Prof. RNDr. Petr Solich, CSc., Prof. Seppo Auriola, MSc. Marko Lehtonen Title of diploma thesis: Development of HPLC method for assessment of stability of amorphous compounds Solid materials can be found in many diverse forms which are distinguishable by different properties. In my thesis, I focus on amorphous solids, their properties, significance, occurrence and, most of all, characterization. The most widely used methods are introduced and described, focusing on their practical use in characterizing polymorphic and amorphous compounds. During the preparation of an amorphous solid, rapid heating and cooling down occurs and therefore degradation can be expected. To prove thermal stability, an HPLC method has been developed and validated for the determination of concentration decrease of an active pharmaceutical ingredient in amorphous state of 8 compounds. The compounds (benzocaine, chlorpropamide, clotrimazole, furosemide, piroxicam, salicylic acid, thiosalicylic acid, and tolbutamide) were determined separately. The method was carried out on a reversed-phase column (1.8µm, 50 × 4.6 mm) maintained at 40řC. The mobile phase was acetonitrile-water containing...
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Exoscopy of sediments of glacigenous accumulation landforms
Křížová, Lenka ; Křížek, Marek (advisor) ; Lisá, Lenka (referee)
This thesis looks at the comparison between grain micromorphology of moraines, debris flows and similar accumulations. Moraine samples were taken in the Černé jezero Lake area, Bohemian Forest, in the Velická dolina Valley, High Tatras, and in the Labský důl Valley, Krkonoše Mts. Samples of debris flows and unverified accumulations were taken in the Důl Bílého Labe Valley, Krkonoše Mts., and further samples of accumulations were obtained from the valley of Prudký potok Stream, Králický Sněžník Mts., the valley of Vražedný potok Stream and Velká Kotlina, Hrubý Jeseník Mts. Sediments were examined under electron microscope and their morphological characteristics and influence of the environment were identified and described. Calculated exoscopic moraine standard was used for comparison of examined forms of relief using distance coefficients, statistical analysis were carried out which identified diagnostic characters for distinguishing moraines and debris flows. There was also calculated exoscopic standard for different types of moraines (frontal, lateral, basal). This research highlighted the differences between moraines and debris flows, and between different types of moraines. The study also proved that typical glacial microtextures, that are generally accepted, occur at similar levels on grains...
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Rainfall-runoff modelling in different hydrogeologic environments
Buchtele, Josef ; Buchtelová, Marie
Simulations of runoff components and sub-surface water storages, using SAC-SMA model, have been carried out for basins in two areas in the Bohemian massif with quite distinct hydrogeological conditions: one is the area with crystalline bedrocks in south Bohemia, the other one belongs to Cretaceous area in north-eastern part of Bohemia. Results show that hydrogeological conditions are important for variability of storage and consequently of outflows. Variability of simulated sub-surface water storages in one basin in Cretaceous also indicate that agrometeorogical and hydrological droughts do not need to appear simultaneously.
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Historical landscape genesis in sub- mountainous areas.
MIHALČÍKOVÁ, Zdeňka
The aim of this work was to define changes in the landscape from 1949 to the present in the area of Zdíkov which is situated near Vimperk in the Bohemian Forest. The representation of elements land use was established- that are forests, arable land, water areas, water-courses, settlements, road network and permanent grassland - on each of the three aerial photographs from the years 1949, 1973 and 1988.The representation of elements land use was compared in each year on the basis of these photographes and the change and transformation of the original character of the landscape were defined in a given time horizon. The results were worked up graphically.
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